PEREZ FARFANTE: ROCK SHRIMP GENUS SICYONIA 



gination flanked by elongate processes and is 

 traversed by a faint suture; in contrast, that of S. 

 penicillata possesses a shallow emargination, 

 often bearing a small anteromedian notch, and is 

 traversed by a deep groove. 



Long after they have been taken from the water, 

 even after years in alcohol, specimens of this 

 species may be readily recognized by a large ocel- 

 lus, consisting of a well-defined yellow center sur- 

 rounded by a broad purplish ring, on the bran- 

 chiostegite. In S. penicillata, as in S. typica, the 

 branchiostegite does not bear a large marking. 



Burkenroad (1938) indicated that all members of 

 S. disedwardsi may be distinguished from those of 

 S. penicillata by the shape of the ocular stylets 

 which in the former, according to him, diverge at 

 the tip; they are straight in the latter. I have found, 

 however, that although the stylets are laterally 

 inclined distally in most of the young of S. dised- 

 wardsi, they are straight in some young and in 

 many adults. 



Commercial importance. — Sicyonia disedwardsi, 

 one of the stubbiest of the rock shrimp occurring in 

 the region, is usually taken with other penaeoids 

 by the shrimp fleets operating in various areas 

 from the Gulf of California to the Golfo de 

 Panama. Because of its size, it appears to have the 

 potential of providing a fishery as has the simi- 

 larly heavy S. brevirostris in the western Atlantic. 



Material. — 242 specimens from 54 lots. 



Mexico— Baja California Sur: 66 69, SIO, 3 

 km SW of Isla Santa Margarita, 48-57 m, 13 

 November 1964, Black Douglas . 5d 69 , SIO, SW 

 of Isla Santa Margarita, 29-40 m, 13 November 

 1964, Black Douglas. 26 19, SIO, NW of Punta 

 Marquez, 37 m, 4 December 1962, H. Perkins and 

 R. Wisner. 126 119, SIO, NW of Todos Santos, 38 

 m, 9 November 1964, Black Douglas. 36 19, 

 YPM, Bahia San Lucas, 15-29 m, 6 May 1936, Zaca 

 stn 135 D-1. 19 , YPM, Bahia San Lucas, 11-37 m, 

 6 May 1936, Zaca stn 135 D-9. 26 29, YPM, off 

 Punta Arena, 92 m, 30 April 1936, Zaca stn 136 

 D-24. 19, YPM, off Punta Arena, 82 m, 3 April 

 1936, Zaca stn 136 D-1. 4d 29, YPM, off Punta 

 Arena, 64 m, 1 May 1936, Zaca stn 136 D-30. 36 

 19, USNM, Bahia La Ventana, 24-27 m, 20 April 

 1939, Strange stn 38. 2619, SIO, off Punta 

 Gorda, 81-84 m, 2 July 1965, C. Hubbs. 46 39, 

 USNM, Canal de San Lorenzo to Isla del Espiritu 

 Santo, 4 April 1960, R. Mercado and G. Pre- 

 ciado. 26 29, SIO, Bahia de la Paz, 55-79 m, 6 

 July 1965, R. Rosenblatt. 36 99, SIO, Canal de 



San Jose, 64 m, 8 July 1965, R. Rosenblatt. 46 

 109, SIO, Punta San Telmo, 10 July 1965, W 

 Baldwin. 86 69, SIO, off W of Isla Monserrate, 

 92-73 m, 12 July 1965, R. Rosenblatt. 26 , SIO, 

 Bahia Concepcion, 4 February 1940, D. 

 Rouch. Id , holotype, YPM, Bahia Concepcion, 3 

 May 1926, Pawnee. 26 29, USNM, 4-6 m, off 

 Punta Concepcion, 12 April 1964, F. Rosales 

 Juarez. 19, YPM, Bahia Santa Ines, 50 m, 13 

 April 1936, Zaca stn 143 D-1. 26 19 , YPM, Bahia 

 Santa Ines, 37 m, 10 April 1936, Zaca stn 141 

 D-4. 19, YPM, Bahia Santa Ines, 13-16 m, 10 

 April 1936, Zaca stn 141 D-1. 26 39 , YPM, Bahia 

 Santa Ines, 50 m, 11 April 1936, Zaca stn 142 

 D-1. 86, SIO, off Santa Rosalia, 35-26 m, 25 

 March 1960, R. Parker. 16 , SIO, S arm of Bahia 

 de los Angeles, 22-37 m, 26 April 1962, R. 

 Rosenblatt. 26 39, AHF, Puerto Refugio, 

 Isla Angel de la Guarda, 38 m, 27 January 1940. 

 Sonora: 16 19, USNM, off Estero de Lobos, 47 

 m, 3 April 1978, Toral Garcia. 19, USNM, 8 

 km off Guaymas, 26 m, April 1980, M. Hatziolos. 

 3d 59, INP, off Punta Rosa, 56 m, 2 April 1978, 

 Toral Garcia. 66 49, USNM, SE of Punta Rosa, 

 54 m, 1 April 1978, Toral Garcia. Sinaloa: 

 Id, USNM, off San Ignacio, 25 May 1962, R. Bush 

 M. 2d, SIO, Isla de Altamura, 22-31 m, 26 

 May 1965, El Golfo II stn 50-6. 19, AHF, off 

 Rio San Lorenzo, 11-24 m, 14 February 1940. 

 Nayarit: Id 59, AHF, off Isla Isabela, 27-46 m, 

 9 May 1939. Jalisco: Id, SIO, Bahia Cha- 

 mela, 27-18 m, 2 April 1973, Agassiz. Colima: 

 19, CAS, off Manzanillo, 17 July 1932, Zaca. 



Costa Rica— Id, AHF, Bahia de Culebra, 5-18 

 m, 24 February 1934. 29, AHF, S of Bahia de 

 Culebra, 18 m, 25 February 1934. 19, SIO, Cabo 

 Blanco, 60 m, 18 April 1973, Agassiz. Id, SIO, 

 Cabo Blanco, 137-145 m, 19 April 1973, C. Hubbs 

 and S. Luke. 19 , UCR, near Cabo Blanco, 245 m, 

 28 April 1973, Enriqueta. Id, UCR, near Cabo 

 Blanco, 249 m, 28 April 1973, Enriqueta. Id, 

 UCR, near Puerto Quedos, 242 m, 26 April 1973, 

 Enriqueta . Id , AHF, 5 km off Isla Manuelita, 146 

 m, 3 June 1973, Velero IV. 19 , AHF, Golfo Dulce, 

 35-88 m, 26 March 1939, Velero IV. 



Panama— 2d 29, USNM, Golfo de Panama, 

 Canopus stn 670. 5d 119, USNM, Golfo de 

 Panama, Canopus stn 126. 2d 29, UP, Ar- 

 chipielago de las Perlas, 11 December 1970, J. M. 

 del Rosario. Id 19, USNM, Isla San Jose, 64 m, 

 23 February 1973, fishermen. 3d 19 , USNM, S of 

 Isla del Rey 44-42 m, 7 May 1967, Pillsbury stn 

 551. 19, AHF, Islas Secas, 46-48 m, 27 March 

 1939. 19, AHF, off Bahia Honda, 55-64 m, 1 



37 



